Alt hold not working

[steelrfan85]

I have autopilot engaged and Alt hold selected but the aircraft doesn’t level out. It’s either in a climb or descent. Of course can’t trim since aircraft is suppose to be holding.

[Victory205]

Are you hitting the NWS button to engage the autopilot mode?

[steelrfan85]

No. The actual switch

[steelrfan85]

I have A/P Ref lit up.

[Victory205]

You set the autopilot mode on the left console then activate it by depressing the NWS button on the stick. You should see the autopilot light go out on the left windscreen indicator panel. You have one more button to push...

[grunf]

I have A/P Ref lit up.

Press Autopilot reference/NWS button

[steelrfan85]

Ok that worked. Thank you.

[rweaves6]

Is it normal for a slight dip in altitude (slight pitch down) when setting alt hold? It seems to want to dip then climb back to where you originally set it. I can’t seem to set alt hold while maintaining a steady alt.

[VampireNZ]

Is it normal for a slight dip in altitude (slight pitch down) when setting alt hold? It seems to want to dip then climb back to where you originally set it. I can’t seem to set alt hold while maintaining a steady alt.

 

 

Ideally you would have the aircraft trimmed for level flight at a stable altitude before engaging AP ALT Hold. Sounds like George is attempting to sort the trim for you as you engage perhaps? Also, don't just hit the NWS button as you pass through the ALT you would like to hold.

I have had no troubles with a smooth transition from trimmed flight to AP.

[rweaves6]

At 24000ft and 350knts, level flight and trimmed level, I get about a 50ft drop on alt hold engagement. It will then climb back to set altitude.